The Recruitment and Diagnosis Core will identify and provide an adequate number of subjects for investigation of the phenomenological and biological correlates of mild Alzheimer's disease (AD). The core will identify patients for the Neuropsychology, Acute Phase Reactants, Family History, Neurochemistry,and Neuropathology Project, the Core will identify cohorts who are nondemented, with mild AD, and with more advanced AD> The Core will also recruited patients with different ages of onset of AD in order to permit study of the familial aggregation and biological correlates of probands with earlier and later ages of onset of the disease. The Core's serial assessments will ensure appropriate group assignment and continued eligibility for all subjects. The Core will also obtain consent to autopsy in order to provide cases for the Neurochemistry and Neuropathology projects. Subjects will be assessed and followed at the Mount Sinai Medica Center, Elmhurst Hospital, the Bronx Veterans Hospital, and the Jewish and Home and Hospital for the Aged. A centralized core facility for patients recruitment and reliable assessment is necessary for efficient and appropriate subject selection and follow up.